Electric snap switch



Jan. 28, 1941. a. J. MEUER ETAL ELECTRIC SNAP SWITCH Filed May 16, 1951 Patented Jan. 28, 1941 UNITED STATES PATENT OFFICE waukee, Wis.,

assignors to Cutler-Hammer,

Inc., Milwaukee, Wis., a corporation of Delaware Application May 16, 1931, Serial No. 537,774

30 Claims.

This invention relates to improvements in electric snap switches.

An object of the invention is to provide a snap switch of extremely small dimensions the parts of which may be readily and quickly assembled.

Another object is to provide novel mounting means for the switch mechanism as a whole.

Another and more specific object is to provide a novel form of snap switch for attachment to and for cooperation with a radio rheostat or similar electrical device.

Another object is to facilitate assembly of the movable switch parts with respect to each other and with respect to the insulating supporting base. 15 Another object is to provide stationary and movable switch contacts of improved form.

Other objects and advantages of the invention will hereinafter appear.

The accompanying drawing illustrates an embodiment of the invention which will now be described, it being understood that the embodiment illustrated is susceptible of modification without departing from the scope of the appended claims.

In the drawing, Figure 1 is a perspective view, in separated relation, of the switch parts and the insulating supporting base therefor.

Fig. 2 is a top plan view of the assembled switch parts in the circuit breaking position thereof.

Fig. 3 is a sectional view on the broken line 3--3 of Fig. 2.

Fig. 4 is a side elevation, with parts broken away, showing our improved switch mechanism attached to a radio rheostat of well known form.

Fig. 5 is a bottom plan view of the metal cover member of the rheostat showing the switch mechanism attached theretocertain other parts of the rheostat being shown in section and in dotted lines, and

Fig. 6 is a plan view of the rheostat and switch mechanism in completely assembled relation. This figure shows the normal size of the switch and rheostat parts-the other figures showing the parts enlarged to diiferent degrees for clarity of illustration.

Referring to the drawing, the numeral I designates an extremely shallow base which may be molded from any suitable insulating material. We prefer to form this base of the phenol formaldehyde condensation product known as "Bakelite. Base III is provided with a relatively shallow recess I I which extends throughout the major portion of one surface thereof,-thus providing a surrounding wall of substantialy uniform thickness or width, except at the diagonally opposed corners I3 and It which are pierced as at I3 and I4 to accommodate suitable attaching elements. Also as shown a portion I2 of the wall at one end 01' base I0 is of increased height to correspond with the particular form of the metal cover member to which the base is to be attached.

The bottom wall of recess II is pierced at spaced points I and IS, the portion I2 of the surrounding wall being widened to provide an arouate surface I2 concentric with opening I5, said surface I2 having at each side thereof vertical shoulders I2 and I2 the planes of which are radial to said opening IS. The movable parts of the switch mechanism comprise a punched and stamped sheet metal contactor I1, a punched and stamped sheet metal actuator I8, and a coiled torsion spring I9 having divergent arms with hook ends 20 and 2| which are respectively adapted to engage said contactor and said actuator. Contactor I1 and actuator I8 are adapted to be mounted upon a common pivot pin 22 above the annular shoulder 23 formed intermediate the length thereof. Thus the contactor I1 is provided with an opening 24 to provide for pivotal engagement thereof with pin 22, said flange 23 providing a bearing surface for said pivoted end of the contactor. Actuator I8 is likewise provided with an opening 25 to provide for pivotal engagement thereof with pin 22 in superimposed relation to the contactor, a downwardly extending flange 25"- (Fig. 3) being provided around said opening 25 to space the contactor and actuator in substantially parallel planes.

Actuator I8 is preferably of somewhat elliptical contour as shown and the same is provided on oposite sides thereof with integral parallel lugs 2land 21. Contactor I1 is provided with an upwardly offset portion 28 for engagement with the stationary contact of the switch, a partially severed portion or lug 29 being located in the plane of said offset portion. The free end 30 of contactor I1 is bent downwardly at a right angle to the ofiset portion 28 whereby the end edge 30*- is normally adapted to slidably engag the bottom wall of recess II. Lug 29 is provided with an opening 29 into which the hook end 20 of spring I9 is freely insertable. Actuator I8 is also provided with an opening I8 into which the hook end 2| of spring I9 may be readily inserted without requiring any bias or compression of the spring if the actuator is turned upon pin 22 to extend at substantially a right angle to contactor When the spring has been thus engaged with contactor I1 and actuator I8, the U-shaped washer 3| is moved laterally into the annular groove 22 of pin 22, the arms of said washer being slidable into position between the arms 28 and 21 of actuator l8. Washer 3! thus acts to prevent upward displacement of the contactor and actuator with respect to pivot pin 22. Thereafter actuator 58 may be moved in a clockwise direction to substantially the position shown in.

Fig. 2 wherein spring I9 is positively held against accidental separation from the contactor and the actuator.

When the aforedescribed parts have been assembled upon pin 22, the hollow end 22 of the latter is inserted through opening i5 until the flange 23 rests upon the bottom wall of recess ll. said end 22 projects beyond the lower face of base It) and through an opening 32- provided in a suitable form of wiring terminal element 32, said end being upset over said terminal element to secure the latter and said pin 22 to the base l0. As best shown in Figs. 3 and 6 the element 32 is seated in a recess formed in a boss 33 upon the lower face of the base. As shown the end portion 32 of element 32 is bent to extend in a plane at right angles to base i0, although it is to be understood that all portions of said terminal member may be located in a single plane if a lesser depth 01 the assembled switch parts is required.

As best illustrated in Figs. 2 and 3 the arcuate portion i2 of the recess wall accommodates the outer edge of washer 3| whereby lateral displacement thereof from pin 22 is prevented. Moreover, the edges 26", 21 of the arms 26 and 21 cooperate with the vertical shoulders I2 l2 to limit oscillatory movement of the actuator IS.

The stationary contact of the switch comprises a metal stud or rivet 34 the convex surface 34' of the head of which extends a predetermined distance above the bottom wall of recess H, and the reduced and hollow end or shank 34 of v which extends through base l0 and through the perforation 35 in a wiring terminal element 35 and is upset over the latter to secure said contact and terminal element to the base.

At that side of the upwardly ofl'set portion 23 of contactor I! which moves into engagement with the convex surface 34' of the stationary contact we preferably provide an integral upwardly angled lug or projection 28 to insure against stubbing of the contactor against the stationary contact. We also preferably provide a downwardly extending lug 2i! upon said upwardly ofiset portion to positively engage the side edge of the contact to limit clockwise movement of the contactor. counterclockwise movement of contactor i8 is preferably limited by engagement thereof with the surrounding wall of recess H at the point I2.

The snap action of contactor i1 afforded by employment of spring l9 will of course be understood by those skilled in the art, but it may be pointed out (Fig. 2, for instance) that upon counterclockwise movement of actuator I8 the spring I9 is compressed until the end 2| of the spring passes slightly to the right of a straight line extending through the center of pin 22 and the other end 20 of the spring, thus shifting the direction of application of the force or energy stored in the spring to effect snap movement of contactor IT in a clockwise direction into engagement with stationary contact 34, such circuit closing position being shown in full lines in Fig. 5. In like manner (Fig. 5) clockwise movement of actuator l8 such as to carry the end 2| of spring is to the left beyond the line extending through pin 22 and the end 20 of the spring will result in snap movement of contactor H in a counterclockwise direction to interrupt the controlled circuit.

The switch mechanism hereinbetore described is obviously of diminutive size, which characteristic alone renders it useful for many purposes where the space requirements of the switch must lie-reduced to a minimum. The switch parts are so correlated as to render the same unusually easy to assemble, while the construction of the switch parts is such as to insure a long life of the switch mechanism as a whole with no likelihood of breakage or derangement thereof while in service. Any suitable arrangement may be provided for effecting oscillatory movement of the actuator IS. The present switch mechanism was, however, primarily designed for use in conjunction with or as a switch attachment for an electrical device such as a radio rheostat having a part movable in opposite directions through an are or angle.

Accordingly the arms 26 and 21 of actuator M are provided with integral projections or extensions 26", 21 which are adapted to be engaged by an element movable arcuately in opposite directions to effect closing and opening of the switch contacts. As shown in Figs. 4 and 5 the movable element may comprise a stud 38, preferably formed of insulating material and carried by the rotatable element 31 of a rheostat of well known form, element 31 being attached in any suitable manner to a shaft 38 which may have a suitable knob or handle (not shown) attached thereto. The rheostat as shown includes a base 39 of suitable insulating material, said base having a rear metal cover member 40 telescoped thereonto and restrained against endwise separation and rotation with respect thereto by means of an element II which is attached to base 39 and which penetrates an opening 42 in the metal cover member and is bent over the latter (Fig. 6).

Cover member 40 is provided with a centrally located substantially cylindrical hollow boss or projection 40 which provides clearance for the rotatable insulating projection 36 aforementioned. Member 40 is also provided with an eccentrically located opening 40' of irregular contour which is overlapped by the walls l2, l2- surrounding recess Ii in base I. The base I0 is rigidly attached to cover member 40 as by means of rivets or eyelets 43. With base H) and its assembled switch parts attached to cover member 40 in the manner aforedescribed, and with the switch parts in off position as shown in Fig. 2 the rheostatic control element 31 is turned to that extreme position thereof wherein the end of the limiting slot 44 (shown in dotted lines in Fig. 5) engages the element 4|, with consequent positioning of insulating stud 36 in the dotted line position 36 Fig. 5. Element 4| is then bent over cover member 40 to secure the parts in completely assembled relation.

Thereafter movement of element 31 through a relatively small angle causes engagement of element 38 with projection 2'! on actuator I! so that movement of element 36 to substantially the position shown at 36 in Fig. 5 will result in snap movement of contactor l1 into engagement with stationary contact 34. Element 31 is free to move in the same direction to its opposite extreme position, wherein the other end 44 of slot 44 engages element 4|. During the final portion of the return movement of element 31 the stud it engages the projection 26' on actuator II to stress spring I! and effect snap movement of contactor I! to open position at substantially the limit of such return movement.

What we claim as new and desire to secure by Letters Patent is:

1. In an electric snap switch, in combination, a pivot pin having an annular shoulder formed intermediate the ends thereof, a punched sheet metal contactor pivotally engaging said pin and adapted to bear against said shoulder, an actuatin element pivotally engaging said pin and adapted to overlie said contactor in spaced relation to the latter, a washer removably interlocked with said pin to retain all of said parts in assembled relation to each other, and a coiled torsion spring having divergent arms with hooked ends to respectively engage said contactor and said actuator, the main body of said spring lying in a plane substantially parallel with and between said contactor and said actuator and the same being adapted to effect snap movement of said contactor in each direction respectively upon predetermined degrees of opposite movement of said actuator.

2. In an electric snap switch, in combination, a pivot pin having an annular shoulder formed intermediate the ends thereof, a punched sheet metal contactor pivotally engaging said pin and adapted to bear against said shoulder, an actuating element pivotally engaging said pin and adapted to overlie said contactor in spaced relation to the latter, a washer removably interlocked with said pin to retain all of said parts in assembled relation to each other, a coiled torsion sprin having divergent arms with hooked ends to respectively engage said contactor and said actuator, the main body of said spring lying in a plane substantially parallel with and between said contactor and said actuator and the same being adapted to effect snap movement of said contactor in each direction respectively upon predetermined degrees of opposite movement of said actuator, an insulating base adapted to receive said pin with the switch parts assembled thereon, said pin having a hollow end portion penetrating said base and projecting therebeyond, a wiring terminal member having a perforation to accommodate said hollow end portion, and said hollow end portion being upset over said terminal member to rigidly and permanently secure the latter and said switch parts to said base.

3. In an electric snap switch, in combination, a pivot pin having an annular shoulder formed intermediate the ends thereof, a punched sheet metal contactor pivotally engaging said pin and adapted to bear against said shoulder, an actuating element pivotally engaging said pin and adapted to overlie said contactor in spaced relation to the latter, a washer removably interlocked with said pin to retain all of said parts in assembled relation to each other, a coiled torsion spring having divergent arms with hooked ends to respectively engage said contactor and said actuator, the main body of said spring lying in a plane substantially parallel with and between said contactor and said actuator and the same being adapted to effect snap movement of said contactor in each direction respectively upon predetermined degrees of opposite movement of said actuator, an insulating base adapted to receive said pin with the switch parts assembled thereon, said pin having a hollow end portion penetrating said base and projecting therebeyond, a

wiring terminal member having a perforation to accommodate said hollow end portion, said hollow end portion being upset over said terminal member to rigidly and permanently secure the latter and said switch parts to said base, a second wiring terminal member, a stationary contact member having an enlarged head portion for cooperation with said contactor, and said stationary contact member having a hollow end portion penetrating said base and said second terminal member and upset over the latter to secure the same to said base.

4. In combination, a recessed molded insulating base, a pivot pin to be fixed thereto, a contactor and an actuator to be pivotally supported by said pin, a coiled torsion spring having arms disposed in parallel planes between said contactor and said actuator and respectively attached thereto, said spring being arranged to effect snap movement of said contactor to opposite extreme positions upon movement of said actuator in reverse directions respectively, and the walls of the recess being formed to limit movements of said actuator and said contactor.

5. In a switch mechanism, a casing, a spindle rotatably mounted therein, an arm on said spindle projecting radially thereof and having in an eccentric relation thereto a projecting pin, an insulating base fixed to said casing and afiording a wall for said casing perpendicular to the axis of said spindle and parallel to the plane of movement of said arm, a pivot pin fixed to said wall afforded by said base and projecting therefrom toward the plane of said arm, and a snap switch mechanism having a contactor and an actuator pivoted on said pin for pivoted movement relatively of one another, said contactor and actuator having an energy storing spring connection which effects snap movements of the former upon movement of the latter in reverse directions through a given range, and said actuator having closely adjacent its pivot parts transiently engageable by said pin on said arm when said arm is moved in either direction through a given part of its range, thereby to efiect reverse operations of said switch.

6. In a switch mechanism, a casing, a spindle rotatably mounted therein, an arm on said spindle projecting radially thereof and having in an eccentric relation thereto a projecting pin, an insulating base fixed to said casing and affording a wall for said casing perpendicular to the axis of said spindle and parallel to the plane of movement of said arm, a pivot pin fixed to said wall afforded by said base and projecting therefrom toward the plane of said arm, and a snap switch mechanism having a contactor and an actuator pivoted on said pin for pivoted movement relatively of one another, said contactor and actuator having an energy storing spring connection which effects snap movements of the former upon movement of the latter in reverse directions through a given range, said actuator having closely adjacent its pivot parts transiently engageable by said pin on said arm when said arm is moved in either direction through a given part of its range, thereby to effect reverse operations of said switch, an externally threaded hollow bushing carried by said casing and through which said spindle is adapted to extend, and a clamping nut on said bushing to provide for one-hole mounting of said casing upon a suitable support.

'7. In a snap switch mechanism of the character described, in combination, an insulating base having walls associated therewith to provide a recess, a pivot pin located in said recess and rigidly attached to said base, a contactor and an actuator each having a part thereof in pivotal engagement with said pin, a stationary contact secured to said base within said recess, a wiring terminal member positioned upon the outer surface of said base and electrically connected with said contact, a coiled torsion spring having divergent arms with bent ends respectively engaged with said actuator and said contactor to effect snap movement of the latter to opposite extreme positions upon movement of the former in reverse directions respectively, said spring also acting to bias said contactor toward said base, said contactor and said contact being cooperatively formed to provide for guiding the former into proper engagement with the latter, a second wiring terminal member positioned upon the outer surface of said base, said switch mechanism being operable to alternately complete and interrupt the electrical connection between said wiring terminal members, and the walls of said recess being formed to limit movements of said actuator and said contactor.

8. In an electric snap switch, in combination, an insulating base having walls associated therewith to provide a recess, a pivot pin located within said recess and rigidly attached to said base, a contactor and an actuator to be pivotally supported by said pin, a coiled torsion spring having arms disposed in substantially parallel planes between said actuator and said contactor and respectively attached thereto, said spring being arranged to effect snap movement of said contactor to opposite extreme positions upon movement of said actuator in reverse directions respectively, and the walls of said recess being formed to limit movements of said actuator and said contactor.

9. In a switch mechanism to be operated by a pin carried eccentrically by an oscillatable mem- 'ber, in combination, an insulating base having in off-centered relation therewith a pivot pin fixed thereto and projecting therefrom, a snap switch mechanism having a contactor and an actuator pivoted on said pivot pin for pivotal movement relatively of one another in parallel planes, said contactor and said actuator having at one side of said pivot pin a self-expanding spring connection which effects by its expansion snap movements of the contactor upon given movements of the actuator, said actuator having closely adjacent the pivot pin parts transiently engageable by the pin on said oscillatable member when the latter is moved in either direction through a given range, thereby to effect selectively reverse operations of said switch mechanism.

10. In a switch mechanism of the character described, in combination, an insulating base having in off-centered relation therewith a pivot pin fixed thereto and projecting therefrom, a snap switch mechanism having a contactor and an actuator pivoted on said pin for pivotal move ment relatively of one another in parallel planes, said contactor and said actuator having at one side of said pivot pin a self-expanding spring connection which effects by its expansion snap movements of the contactor upon reverse movements of the actuator, a pivoted operating arm overlying said actuator, said arm being oscillatable in a plane parallel to the plane of movement of said actuator and having a pin extending therefrom eccentrically and perpendicularly thereof, and said actuator having closely adjacent the pivot pin parts transiently engageable by said pin on said arm when said arm is moved in either direction through a given part of its range thereby to effect reverse operations of said switch mechanism.

I 11. In a switch mechanism of the character described, in combination, a one-piece insulating base, a pivot pin having a portion thereof penetrating said base and rigidly attached thereto, a contactor and an actuator each having a part thereof in pivotal engagement with said pin for support by the latter, a stationary contact secured to the inner surface of said base, a wiring terminal member positioned upon the outer surface of said base and electrically connected with said contact, a self-expanding spring interposed between said actuator and said contactor at one side of said pivot pin, said spring being arranged to effect by its expansion snap movements of said contactor to opposite extreme positions upon movements of said actuator in reverse directions respectively, said spring also acting to bias said contactor toward the inner surface of said base, said contactor and said contact being cooperatively formed to provide for guiding the former into proper engagement with the latter, and a second wiring terminal member positioned opon the outer surface of said base, said switch mechanism being operable to alternately complete and interrupt an electrical connection between said wiring terminal members.

12. In a switch mechanism of the character described, in combination, an insulating base, a pivot pin having a portion thereof penetrating said base and rigidly attached thereto, a contactor and an actuator each having a part thereof in pivotal engagement with said pin, a stationary contact secured to the inner surface of said base, a wiring terminal member positioned upon the outer surface of said base and electrically connected with said contact, a self-expanding spring interposed between said actuator and said contactor at one side of said pivot pin, said spring being arranged to effect by its expansion snap movement of said contactor to opposite extreme positions upon movement of said actuator in reverse directions respectively, said spring also acting to bias said contactor toward the inner surface of said base, said contactor and said contact being cooperatively formed to provide for guiding the former into proper engagement with the latter, a second wiring terminal member positioned upon the outer surface of said base, said switch mechanism being operable to alternately complete and interrupt an electrical connection between said wiring terminal members, said actuator having a pair of spaced arms, and an operating member movable in opposite directions throughout a predetermined range, said operating member having a transient lost motion driving connection with said actuator to provide for closed-circuit and open-circuit operation of said switch mechanism during movements of said operating member in reverse directions respectively through a relatively small portion of its range.

13. An electric snap switch of relatively small dimensions, comprising a molded insulating base having a relatively shallow recess extending throughout the major portion of one face thereof, a pair of wiring terminal members positioned upon the opposite face of said base, a pivot pin at one end of said recess, said pin having a shouldered hollow end penetrating said base and one of said terminal members and riveted over the latter to secure said parts to each other, a stationary contact at the other end of said recess, said contact having a shouldered hollow end penetrating said base and the other terminal member and riveted over the latter, a punched sheet metal contactor pivotally mounted on said pin, an actuating element also pivotally mounted on said pin, and a coiled torsion spring having arms the hooked end portions of which are respectively engaged with said actuator and said contactor to effect snap movements of the latter into and out of engagement with said contact upon given oppositely directed movements of the former.

14. An electric snap switch of relatively small dimensions, comprising a molded insulating base having a relatively shallow recess extending throughout the major portion of one face thereof, a pair of wiring terminal members positioned upon the opposite face of said base, a pivot pin at one end of said recess, said pin having a shouldered hollow end penetrating said base and one of said terminal members and riveted over the latter to secure said parts to each other, a stationary contact at the other end of said recess, said contact having a shouldered hollow end penetrating said base and the other terminal memher and riveted over the latter, a punched sheet metal contactor pivotally mounted on said pin, an actuating element also pivotally mounted on said pin, a coiled torsion spring having arms the hooked end portions of which are respectively engaged with said actuator and said contactor to effect snap movements of the latter into and out of engagement with said contact upon given oppositely directed movements of the former, a U-shaped washer laterally engaged with said pin to retain said actuator and said contactor in assembled relation, the wall of said recess being formed to prevent displacement of said washer, and said actuator having spaced lugs formed thereon to provide a lost motion driving connection between the same and a suitable operating member.

15. An electric snap switch of relatively small dimensions, comprising a molded insulating base having a relatively shallow recess extending throughout the major portion of one face thereof, a pair of wiring terminal members positioned upon the opposite face of said base. a pivot pin at one end of sa d recess. said pin having a shouldered hollow end penetrating said base and one of said terminal members and riveted over the latter to secure said parts to each other. a stationary contact at the other end of said recess. said contact having a shouldered hollow end penetrating said base and the other terminal member and riveted over the latter. a punched sheet metal contactor pivotally mounted on said pin, an actuating element also pivotally mounted on said pin, a coiled torsion spring having arms the hooked end portions of which are respectively engaged with said actuator and said contactor to effect snap movements of the latter into and out of engagement with said contact upon given oppositely directed movements of the former, a U-shaped washer laterally engaged with said pin to retain said actuator and said contactor in assembled relation, the wall of said recess being formed to prevent displacement of said washer, said actuator having spaced lugs formed thereon to provide a lost motion driving connection between the same and a suitable operating member, and a metal shell or cover member to which said insulating base is rigidly attached, said shell having an opening to provide clearance for said lost motion driving connection.

16. In an electric snap switch, incombination, an insulating base member having a recess, a pivot pin secured to said base and projecting upwardly from the bottom wall of said recess, a contact member secured to said bottom wall and having a convex end portion projecting upwardly therefrom, a punched and stamped sheet metal contactor having one end portion thereof pivotally supported by said pin, the other end portion of said contactor being offset upwardly to normally lie in a plane slightly below the convex end of said contact, said offset portion hav ing an upwardly angled edge to facilitate engagement thereof with said contact, and said offset portion also having a downwardly extending lug cooperable with said contact to limit movement of said contactor in one direction.

17. In an electric snap switch, in combination, an insulating base member having a recess, a pivot pin secured to said base and projecting upwardly from the bottom wall of said recess, a contact member secured to said bottom wall and having a convex end portion projecting upwardly therefrom, a punched and stamped sheet metal contactor having one end portion thereof pivotally supported by said pin, the other end portion of said contactor being offset upwardly to normally lie in a plane slightly below the convex end of said contact, said offset portion having an upwardly angled edge to facilitate engagement thereof with said contact, said offset portion also having a downwardly extending lug cooperable with said contact to limit movement of said contactor in one direction, said contactor being engageable with a side wall of said recess to limit movement thereof in the reverse direction, and spring means for effecting snap movement of said contactor in opposite directions respectively.

18. In an electric snap switch, in combination, an insulating base member having a recess, a pivot pin secured to said base and projecting upwardly from the bottom wall of said recess, a contact member secured to said bottom wall and having a convex end portion projecting upwardly therefrom, a punched and stamped sheet metal contactor having one end portion thereof pivotally supported by said pin, the other end portion of said contactor being bent downwardly at right angles to the main body thereof whereby its edge is adapted for sliding engagement with said bottom wall, the intermediate portion of said contactor being offset upwardly to normally lie in a plane slightly below the convex end of said contact, said offset portion having an upwardly angled edge to facilitate engagement thereof with said contact. said offset portion also having a downwardly extending lug cooperable with said contact to limit movement of said contactor in one direction, said contactor being engageable with a side wall of said recess tolimit movement thereof in the reverse direction, and spring means for effecting snap movement of said contactor in opposite directions respectively, said spring means also acting to bias said contactor toward said bottom wall of the recess.

19. In combination. a recessed molded insulating base, a contactor oscillatably supported within said recess, an actuator also oscillatably supported within said recess in upwardly offset relation to the bottom wall of the latter, said actuator having spaced lugs adapted for transient engagement alternately by an oscillatable operating member of suitable form, a stationary contact member located within said recess, a coiled spring interposed between the free end of said contactor and said actuator to effect snap movements of said contactor into and out of engagement with said stationary contact upon movements of said actuator in reverse directions respectively, a plurality of wiring terminal members secured to said insulating base and exposed on the outer surface of the latter, and

means comprising a plurality of metal eyelets for attaching said insulating base at spaced points to an electrical device in a relation to provide for concealment of said recess and the switch parts located therewithin.

20. An electric snap switch of relatively small dimensions, comprising a molded insulating base having a relatively shallow recess extending throughout the major portion of one face thereof, a contactor and an actuator pivotally supported within said recess, said actuator having spaced lugs formed thereon to provide a lost motion driving connection between the same and a suitable operating member, a spring interposed between the free end of said contactor and said actuator to effect snap movements of the former in reverse directions upon movements of the latter in opposite directions respectively, the walls of said recess being adapted to limit the aforementioned movements of said contactor and said actuator, and means for attaching said insulating base to a suitable support.

21. In combination, a recessed molded insulating base, a terminal member positioned upon the outer surface of said base, a pivot pin having a portion thereof penetrating said base and said terminal member and upset over the latter to secure said parts to each other, a contactor and an actuator to be pivotally supported by said pin, a stationary contact secured within said recess and having the contact surface thereof spaced upwardly from the bottom wall of said recess, a coiled spring interposed between said actuator and said contactor, said spring being arranged to effect snap movement of said contactor to opposite extreme positions upon movement of said actuator in reverse directions respectively, said spring also acting to bias the free end of said contactor to a plane slightly below said contact surface, said contactor having an upwardly angled lug at the edge thereof adjacent to said contact to guide the free end of the former into engagement with said contact surface and the walls of said recess being formed to limit movements of said actuator and said contactor.

22. An electric snap switch comprising an insulating base having a pair of wiring terminal members positioned in spaced relation to each other upon one face thereof, a pivot pin having a hollow end portion penetrating said base and one of said terminal members and upset over the latter to secure said parts in assembled relation, a punched and stamped sheet metal contactor pivotally supported upon the opposite face of said base by said pivot pin, a stationary contact having a convex head portion positioned upon the last mentioned face of said base and having a hollow end penetrating the latter and the other of said terminal members and upset over the latter to secure said parts in assembled relation, an actuating element also pivotally supported upon said last mentioned face of said base, and a coiled torsion spring having divergent arms with hooked end portions to be respectively engaged with said actuator and said contactor to effect snap movements of the latter into and out of engagement with said stationary contact upon given oppositely directed movements oi the former.

23. In an electric snap switch, in combination,

an insulating base, a pair of wiring terminal elements positioned in spaced relation to each other on one face of said base, a stationary contact comprising a rivet having a head portion positioned upon the opposite face of said base, said rivet having a hollow shank penetrating said base and one of said terminal elements and 119- set over the latter to rigidly secure said parts in assembled relation, a punched and stamped sheet metal contactor pivotally supported upon the last mentioned face of said base, the pivotal supporting means for said contactor including a pin having a hollow end portion penetrating said base and the other of said terminal elements and upset over the latter to rigidly secure said parts in assembled relation, an actuating element for said contactor also pivotally supported upon said last mentioned face of said base, a coiled torsion spring having divergent arms with bent ends to respectively engage said actuator and said contactor to effect snap movements of the latter into and out of engagement with said stationary contact upon given oppositely directed movements of the former, said spring acting to bias the free end portion of said contactor toward said base whereby said free end portion is normally movable in a plane slightly below the upper surface of said contact, and said free end portion having an upwardly angled edge to facilitate sliding engagement thereof with said contact. 24. In combination, an electrical resistance varying device having a member movable throughout a relatively wide range with reference to a given axis, a projecting element mounted upon said member eccentrically of said axis, a relatively shallow recessed molded insulating base, a snap switch mechanism located within the recess in said base and including an oscillatable actuating element, a metal cover member for saidlresistance varying device attached thereto directly, means penetrating said cover member and said base at a plurality of spaced points whereby the latter is rigidly secured to the former in a relation to provide for concealment of the switch parts with said actuating element oscillatable in a plane parallel to the plane of movement of said projecting element, said cover member having an opening therein to provide clearance for part of said actuating element, and said projecting element having a transient lost motion driving connection with said part of said actuating element to provide for operation of the switch parts to closed and/or opencircuit position during movement of said movable member in reverse directions respectively through a relatively small portion of its range.

25. In combination, a recessed molded insulating base, a terminal member positioned upon the outer surface of said base, a pivot pin having a portion thereof penetrating said base and said terminal member and having a part in clamping engagement with the latter, a contactor and an actuator each having a part thereof in pivotal engagement with said pin, a stationary contact secured within said recess and having a surface thereof spaced upwardly from the bottom wall of said recess, a second terminal member positioned upon the outer surface of said base and electrically connected with said contact, a coiled spring interposed between said actuator and said contactor, said spring being arranged to effect snap movement of said contactor to opposite extreme positions upon movement of said actuator in reverse directions respectively, said spring also acting to bias the free end of said contactor to a plane slightly below said contact surface, said contactor and said contact being cooperatively formed to provide for guiding the free end of the former into engagement with said contact surface, and the walls of said recess being formed to limit movements of said actuator and said contactor.

26. In a combined volume control and switch, in combination, an assembly comprising a resistor, wiring terminals, means including a rotatable member to vary a circuit connection of said resistor and a supporting base for said resistor, said wiring terminals and said means, another assembly comprising a switch, wiring terminals and a supporting base for said switch and terminals, said rotatable member having an operative connection with said switch, the connection between said rotatable member and said switch being of a transient character and comprising a pivoted element of said switch assembly having its pivotal axis parallel to and spaced laterally from the axis of rotation of said rotat- .'able member, said pivoted element having relatively close to its pivot means extended axially of said element for transient engagement by said rotatable member, and a housing including the bases of said assemblies to support and fully enclose said resistor, substantially all of its said circuit varying means, said switch and said operative connection, said rotatable member extending outside of said housing.

27. The combination with an electrical resistance varying device having a member rotatable to opposite extreme positions, of a projecting element mounted eccentrically upon said member, a metallic cover member for said resistance varying device directly attached thereto, said cover member having an opening formed in its end wall, a relatively shallow recessed molded insulating base member adapted to overlie said opening and rigidly secured to said cover member,

and a snap switch mechanism carried in its entirety by said base member and enclosed thereby, said switch mechanism including a pivoted actuating element with which said projecting element has transient driving engagement in different positions of said rotatable member whereby operation of said switch mechanism is effected, said actuating member having its pivotal axis parallel to the'axis of said rotatable member.

28. In a combined volume control and switch unit, in combination, an assembly comprising a resistor, wiring terminals, means including a rotatable member to vary a circuit connection of said resistor and a supporting base for said resistor, said terminals and said means, another assembly comprising a switch, wiring terminals and a supporting base for said switch and latter terminals, said switch including a pivoted actuating element movable in a plane perpendicular to the axis of said rotatable member and said rotatable member having offset laterally from its axis a projection for transient engagement with said actuating element of said switch and a builtup housing for said assemblies, said housing including the bases of said assemblies and also including a metal wall interposed between said two assemblies and having formed in it an opena ing, said switch actuating element having rigid means extending through said opening in said metal wall relatively close to the pivot of said element to be transiently engaged by said projection of said rotatable member beyond said metal wall, said rotatable member being in part enclosed by said housing but having a part extending outside of said housing.

29. The combination with an electrical resistance varying device, said device having a member rotatable in opposite directions between extreme positions to vary the value of active resistance, of a projecting element mounted upon said member and movable thereby through an arcuate path, a stamped sheet metal cover member for said resistance varying device, said cover member comprising as a unitary part thereof a wall having an opening formed therein and arranged in unsymmetrical relationship to the contour thereof, a relatively shallow recessed molded'insulating base, said base being fitted closely against said wall and being rigidly attached.

thereto in a relation to overlie said opening, and a snap switch mechanism having the switch parts thereof located within the recess in said base member and having the wiring terminal parts thereof exposed upon the outer surface of said base, said switch mechanism including an oscillatable actuating element extending into said cover member through said opening and having a pair of spaced upstanding arms with which said projecting element has transient driving engagement in different positions of said rotatable member whereby operation of said switch mechanism is effected.

30. The combination with a rheostat having a shaft rotatable in opposite directions between limits to effect variation in the value of active resistance, a stud mounted eccentrically of the axis of said shaft and movable by the latter in an arcuate path, a one-piece cup-shaped stamped sheet metal cover secured to said rheostat, said cover having an opening formed in a wall thereof and located eccentrically with respect to the contour of said cover, a relatively small and relatively shallow recessed molded insulating base, the recessed face of said base being snugly fitted against the outer surface of said cover and being rigidly attached thereto in a relation to overlie said opening, and a snap switch mechanism having the switch parts thereof located within the recess in said base and having the wiring terminal parts thereof exposed upon the outer surface of said base, said switch mechanism including an oscillatable contactor and an oscillatable actuating element therefor with a spring member interposed therebetween, a pivot member common to said contactor and said actuating element, said actuating element extending into said cover through said opening and having a pair of spaced upstanding arms with which said stud has transient driving engagement in different rotary positions of said shaft whereby operation of said switch mechanism is effected, the walls oi the recess in said base acting to limit oscillatory movements of said contactor and said actuating element in opposite directions respectively.

J. ME'UER.

GEORGE W'IILIAM C. STEVENS. 

